1. Technical Field
The inventive concept relates to a data read circuit, and more particularly, to a data read circuit for performing a data read operation by using a plurality of reference voltages, a non-volatile memory device including the data read circuit, and a method of reading data from the non-volatile memory device.
2. Discussion of the Related Art
Semiconductor memory is an electronic data storage device, implemented on a semiconductor-based integrated circuit. Examples of semiconductor memory devices may include volatile memory devices and non-volatile memory devices. Volatile memory devices require power to maintain the stored information, non-volatile memory devices do not.
Examples of non-volatile memory devices may include a Phase Change Random Access Memory (PRAM), a Resistive Random Access Memory (RRAM), a Magnetic Random Access Memory (MRAM), and a Ferroelectric Random Access Memory (FRAM). PRAM stores data by altering the state of the matter from which the device is fabricated, RRAM uses a variable-resistance material, for example, complex metal oxides whose resistance value change when voltage is applied, to store data, MRAM data is stored by magnetic storage elements formed from two ferromagnetic plates, and FRAM uses a ferroelectric layer to store data.
Semiconductor memory devices with improved performance are being developed at an almost frantic pace. Improved performance may by achieved by increasing a degree of integration, increasing operating speed, or guaranteeing data reliability. However, due to a number of factors such as process variations that occur when the semiconductor memory device is fabricated or a variation in signals provided to circuits for operating the semiconductor memory device (for example, circuits for writing or reading data), performance degradation may still occur. Therefore, there is a need for a semiconductor memory device capable of reducing performance degradation.